Intensifying cylinder

Abstract

An intensifier is operable to supply force and includes a housing defining a cavity. A ram is slidably positioned within the cavity and partially extends from the housing. The ram is moveable between retracted and extended positions along a longitudinal axis. First and second links are rotatably coupled to one another about an axis of rotation and are selectively moveable between retracted positions where the axis of rotation is not axially aligned with the ram and partially extended positions where the axis of rotation is axially aligned with the ram. The intensifier includes a plurality of power pistons axially aligned with each other and the ram. The power pistons are selectively operable to provide an output force to the ram when the first and second links are in the partially extended positions.

1. An intensifier for supplying force, the intensifier comprising:
 a housing defining a cavity; 
 a ram slidably positioned within the cavity and partially extending from the housing, the ram being moveable between retracted and extended positions along a longitudinal axis; 
 first and second links rotatably coupled to one another about an axis of rotation, the links being selectively moveable between retracted positions where the axis of rotation is not axially aligned with the ram and partially extended positions where the axis of rotation is axially aligned with the ram, wherein the first link includes a slot in receipt of a pin fixed to the housing to restrict the first link from rotating when in the partially extended position; and 
 a plurality of power pistons axially aligned with each other and the ram, the plurality of power pistons being selectively operable to provide an output force to the ram when the first and second links are in the partially extended positions. 
 
   
   
     2. The intensifier of  claim 1  further including a forward connecting rod having a first end pivotally coupled to the first link and a second end fixed to the ram. 
   
   
     3. The intensifier of  claim 2  wherein the forward connecting rod is axially moveable collinearly with the ram. 
   
   
     4. The intensifier of  claim 3  further including a rear connecting rod having a first end pivotally coupled to the second link and a second end driven by the plurality of power pistons. 
   
   
     5. The intensifier of  claim 4  further including a first link pin pivotally interconnecting the forward connecting rod and the first link, a second link pin pivotally interconnecting the first link and the second link and a third link pin pivotally interconnecting the second link and the rear connecting rod. 
   
   
     6. The intensifier of  claim 5  wherein the first and third link pins are aligned along an axis of translation of the ram when the first and second links are in either of the retracted and partially extended positions. 
   
   
     7. The intensifier of  claim 5  wherein the second link pin is positioned in alignment with the ram axis of translation when the first and second links are in their partially extended positions. 
   
   
     8. The intensifier of  claim 1  wherein the pin is clear of the slot when the first link is in the retracted position. 
   
   
     9. The intensifier of  claim 8  wherein the first link includes a cam surface engaging the pin to cause the first link to rotate during movement from the partially extended position to the retracted position. 
   
   
     10. The intensifier of  claim 9  wherein the first link includes another cam surface engaging another pin having a position fixed relative to the housing to cause the first link to rotate during movement from the retracted position to the partially extended position. 
   
   
     11. The intensifier of  claim 1  wherein the ram is coupled to a piston and the piston is in receipt of pressurized fluid before the power pistons are acted on by pressurized fluid as the ram moves from the retracted to the extended position. 
   
   
     12. The intensifier of  claim 1  wherein the plurality of power pistons include an outer surface having one of a round, oval or elongated shape. 
   
   
     13. The intensifier of  claim 1  wherein the first and second links are positioned in a sealed cavity containing lubrication. 
   
   
     14. The intensifier of  claim 1  further including an anti-ram rotation rod mounted within the cavity to restrict the ram from rotation. 
   
   
     15. An intensifier for supplying force to a workpiece, the intensifier comprising:
 a housing; 
 a ram at least partially slidably positioned within the housing, the ram being moveable between a retracted position and an extended position and being adapted to supply force to the workpiece; 
 a plurality of pistons selectively operable to provide force to the ram; and 
 a valve rod fixed to the ram, positioned within the housing and operable to open a passageway and supply pressurized air to the plurality of pistons after the ram has moved to an intermediate position between the extended position and the retracted position, wherein the valve rod extends substantially parallel to and transversely offset from the ram. 
 
   
   
     16. The intensifier of  claim 15  further including a piston fixed to the ram and slidably positioned within a cavity formed in the housing, the passageway having an opening in communication with the cavity. 
   
   
     17. The intensifier of  claim 16  further including a linkage having first and second pivotal links interconnecting the plurality of pistons and the ram. 
   
   
     18. The intensifier of  claim 17  wherein a pivot point between the first and second links moves from a positioned aligned with an axis of translation of the ram to a position offset from the axis when the ram moves from the extended position to the retracted position. 
   
   
     19. The intensifier of  claim 15  wherein each of the pistons is fixed to a hollow rod including a substantially transversely extending passageway in communication with one another. 
   
   
     20. The intensifier of  claim 15  further including an anti-ram rotation rod mounted within the housing to restrict the ram from rotation. 
   
   
     21. A method of operating an intensifier having a longitudinally translatable ram, axially and pivotally moveable first and second links and a plurality of power pistons, the method comprising:
 applying pressurized air to the ram; 
 moving the ram from a retracted position to a partially extended position; 
 moving the first and second links from retracted positions where the first and second links are not coaxially aligned to partially extended positions where the first and second links are substantially coaxially aligned with the ram; 
 positioning a pin within a slot formed in the first link to restrict the first and second links from rotation when in the partially extended positions; and 
 applying pressurized air to the plurality of power pistons to provide a force acting on the first link, the second link and the ram to output an amplified force and move the ram to a fully extended position. 
 
   
   
     22. The method of  claim 21  further including opening an internal valve to supply pressurized air to the plurality of power pistons after the first and second links are in the partially extended position. 
   
   
     23. The method of  claim 21  further including restricting the ram from rotation while moving between the retracted and fully extended positions.